Ait-Nouri spent last season on loan at the Molineux Stadium, making 24 appearances in all competitions, including 21 in the Premier League and scored one goal.
The 20-year-old France under-21 international left back has signed a five-year contract with Bruno Lage’s men after impressing in his temporary spell last term.
Ait Nouri is Wolves’ third summer signing following the acquisitions of Francisco Trincao on loan from Barcelona and Colombia defender Yerson Mosquera.
Technical director Scott Sellars said: “We think Rayan is a great signing for the football club. He proved last season that he’s a very talented player, with lots of potential – I thought he did well and kicked on towards the end of the season. He’s a player who is only going to get better, he’s a good boy, who works hard, and settled in well here.
“We’ve used the loan before buying approach well in the past, with people like Jonny and Raul [Jimenez]. I think it’s a great way for both parties to get to know each other, to see if they can adapt and enjoy English football, and we get a chance to have a look first, and see if a deal can be done.
“In Rayan’s case, he got a lot of minutes because both Jonny and Marcal suffered injury problems last season, so he had lots of games in the Premier League to show his quality.
“At his age, he’s got a lot to learn still, a lot of work on, and I’m sure with us he’ll develop. He has great quality going forward, we all remember his goal on his debut, so he’s got a lot going for him, as well as areas to develop, like all players.”
